class_docstr: Widget for proportionally dividing its internal area into a grid.
  
  This widget will automatically set the position and size of child widgets
  according to provided constraints.
  
  Parameters
  ----------
  spacing : int
      Spacing between widgets.
  **kwargs : dict
      Keyword arguments to pass to `Widget`.
code: def layout_array(self):
      locs = -1 * np.ones(self.grid_size, int)
      for key in self._grid_widgets.keys():
          r, c, rs, cs = self._grid_widgets[key][:4]
          locs[r : r + rs, c : c + cs] = key
      return locs
  
imports: from __future__ import division
  import numpy
  from vispy.geometry import Rect
  from .widget import Widget
  from .viewbox import ViewBox
  from kiwisolver import Solver, Variable, UnsatisfiableConstraint
label_desc: Use image node_id 11 for calling the Grid obj's underlying member method code with example usage: obj.layout_array() and returns: locs